Water is a limited resource and is often managed or analyzed for at least environmental, economic, and health reasons. In fact, the water quality of oceans, rivers, reservoirs, and other bodies of water has an impact not only on the environment but also on the ability to use these resources effectively and efficiently. The quality of the water may also impact the cost associated with water management or water analysis.
The quality of water can be affected by many factors. The quality of water can be affected, for instance, when nutrients and salts are naturally added to the water from the environment. At the same time, the quality of water can also be affected from other activities such as sewage discharge, agriculture, mining, land development, dredging, or the like.
The quality of water is often determined by measuring characteristics or attributes of the water. Turbidity, pH, dissolved oxygen, temperature, and conductivity are commonly measured indicators of water quality. Each of these indicators provides certain information.
Turbidity, for example, is a measurement of the opaqueness of water. As the amount of suspended materials in the water increases, the water becomes murkier or less clear. In many bodies of water, for example, turbidity often increases after rainfall and flooding due in part to soil erosion.
The suspended materials impact the quality of the water in various ways. They may absorb nutrients or heavy metals and cause sedimentation, for example. Unless remedied, water having high turbidity can lead to health problems.
As with turbidity, high or low levels of pH, dissolved oxygen, temperature and conductivity can have adverse effects on wildlife, fish populations, human health, and esthetics. Unfortunately the cost of remediating water quality problems can be expensive.
Thus, measurements of water quality become tools that aid the analysis of water quality. Measuring the attributes or characteristics of water like turbidity of water is often performed using sensors. Unfortunately, sensors are subject to fouling (e.g., algae growth, mineral deposits, etc.). Fouling can increase the cost of water management because fouling can interfere with the operation of the sensor over time. As a result, it is necessary to either perform maintenance on the sensors or replace them with new sensors. In either case, the cost associated with measuring water quality is adversely affected.